<template>
  <div class="number-container d-flex justify-content-center align-items-center">
    <!-- 减 1 的按钮 -->
    <button type="button" class="btn btn-light btn-sm" @click="sub">-</button>
    <!-- 购买的数量 -->
    <span class="number-box">{{ num }}</span>
    <!-- 加 1 的按钮 -->
    <button type="button" class="btn btn-light btn-sm" @click="add">+</button>
  </div>
</template>

<script>
import bus from '@/components/eventBus.js'

export default {
 props:['num','id'],
 methods:{
   add(){
     const obj = {id:this.id , value:this.num + 1}
     bus.$emit('fnadd',obj)
   },
   sub(){
     if(this.num === 0) return
     const obj = {id:this.id , value:this.num - 1}
     bus.$emit('fnadd',obj)
   }
 }
}
</script>

<style lang="less" scoped>
.number-box {
  min-width: 30px;
  text-align: center;
  margin: 0 5px;
  font-size: 12px;
}

.btn-sm {
  width: 30px;
}
</style>
